In my U.S. Pat. No. 5,511,497 I disclosed a digger for facilitating the application of a material such as a supplement to a mushroom bed. As disclosed therein, the digger includes a rotating shaft having a plurality of outwardly extending tines which dig into the mushroom bed as the digger is being pulled longitudinally over the bed. The shaft is mounted in a housing or shroud which contains most of the other elements of the digger, including the motorized drive assembly for the shaft. A compartment containing the materials to be applied is also connected to the shroud and includes various hoses which lead from the compartment. Air is utilized to dispense the material from the compartment by feeding the air through tubing into a manifold at the top of the compartment. The manifold has a plurality of individual discharge hoses each having a flow control valve. Each hose leads to a head at the bottom of the compartment. The top of each head includes openings which function as a venturi opening to draw the supplement material into the head and then the supplement/air flow continues through a set of tubes, each of which is associated with the venturi openings. Each of these tubes leads to a respective delivery head mounted to the shroud. The supplement is discharged from ports in the delivery head at a location near the rotating tines so that the supplement is applied in the area of the compost where the tines are performing the digging act.
It would be desirable if a digger as disclosed in my patent could be provided with some structure to assure proper delivery of the material being applied to the mushroom bed.
It would also be desirable if some structure could be provided to eliminate problems with digger shaft failure.